High-density information discs, particularly highly conductive capacitance electronic discs, are lubricated to reduce wear of the playback stylus. Suitable lubricants are known. A methyl alkyl siloxane having the formula ##STR2## wherein R.sub.1 and R.sub.2 are alkyl groups of 4-20 carbon atoms, x is an integer of 2-4, y is an integer of 0-2 and wherein the sum of x and y is 4 or less, is particularly preferred because of its excellent lubricity, long wear, and stability to the environment over long periods of time.
However, the siloxanes alone do not overcome a problem of moisture-sensitivity of the disc. The discs are compression-molded from heavily filled plastics that contain a variety of ingredients including for example internal and external lubricants, flow modifiers, conductive fillers and stabilizers. After compression-molding, the disc surface is coated with water-soluble salts that form during the molding process. When the disc is exposed to moisture from the environment, the salts dissolve in the water, and when the water evaporates, the salts reappear, but now as discrete salt deposits rather than as an overall film. These deposits are sufficiently large to interfere with playback of the disc and must be removed. Cleaning the disc to remove the water-soluble salts helps, as is disclosed in U.S. Pat. No. 4,383,961 herein incorporated by reference. Various polar additives have also been added to the lubricant in an effort to reduce moisture sensitivity, known as "carrier distress". For example, preferred dopants, because of their excellent results, are bis(hydroxyalkyl)disiloxanes. These additives, while very effective, have the drawback that they are expensive because of the careful purification procedures that must be performed to make them useful for this application. These procedures are detailed in U.S. Pat. Nos. 4,355,062 and 4,391,720.
Thus the search for alternative additives that are as effective as the bis(hydroxyalkyl)disiloxanes in reducing moisture sensitivity but are less expensive has continued.